I think it's late 80's, a father finds out his daughter joins a cult, possibly a satanic cult. I can't remember for sure. I was thinking it had a title like Gatherings or Rituals or something. But those were 2 different horror movies, not this one. I think it was a one word title something similar to that. I think I remember the movie cover having a pitch fork on it, but I can't remember for sure.

Does "Thirst" end with the woman being tricked/forced/"driven to" killing her lover/love interest and then going mad? If so it may be another odd film I think I saw when I was in Japan, that I've wondered about for a while. I've thought about starting a thread, but couldn't think of enough details to make posting a question worthwhile. Thanks.

Does "Thirst" end with the woman being tricked/forced/"driven to" killing her lover/love interest and then going mad? If so it may be another odd film I think I saw when I was in Japan, that I've wondered about for a while. I've thought about starting a thread, but couldn't think of enough details to make posting a question worthwhile. Thanks.

No, it's definitely not "Oldboy", which has nothing to do with vampires and the main character isn't a woman. The movie Steve linked to definitely sounds like it's the film I was looking for. It's just that the plot summaries on IMDB don't mention the specifics of what happened at the end and that is the scene I remember the most.